Analyzed case-studies include DMA from two different WDS from Lisbon and Setubal districts in Portugal. To identify the subset of DMA where temperature and rainfall may have a higher influence on urban water consumption, billing and socio-demographic variables were explored for each DMA according to the criteria described in Table 1. Billing variables include total domestic billed consumption, domestic billed consumption in the third and fourth tariff levels and total public billed consumption. DMA were selected in order to ensure that the main component of urban consumption (Almeida et al. 2006) – domestic – is predominant in these network areas. An additional criterion was considered in terms of the proportion of domestic consumption in the higher tariff levels in order to focus the analysis on areas with higher consumption per customer.

Table 1

Criteria used for DMA selection in terms of billed consumption and economic characteristics

Billed and economic parametersDescriptionCriteria
Domestic billed consumption (%) Ratio between annual domestic billed consumption and the total annual billed consumption. >50%
Domestic billed consumption in the 3rd and 4th tariff levels (%) Ratio between annual domestic billed consumption in the 3rd and 4th tariff levels and the total annual domestic billed consumption in all tariff levels (1st to 4th tariff levels). According to IRAR (2009), the 3rd tariff level is defined between 15 to 25 m3/month and the 4th tariff level is defined for volumes higher than 25 m3/month. >5%
Public billed consumption (%) Ratio between annual public billed consumption and the total annual billed consumption. >5%
Economic mobility index (%) Ratio between the number of residents employed in the tertiary sector and the number of total residents. Previous theoretical models used the income variable to predict residential water demands. Cole (2004) indicates that higher levels of income can indicate higher living standards, which could imply a higher quantity of water consumption. >70%
Billed and economic parametersDescriptionCriteria
Domestic billed consumption (%) Ratio between annual domestic billed consumption and the total annual billed consumption. >50%
Domestic billed consumption in the 3rd and 4th tariff levels (%) Ratio between annual domestic billed consumption in the 3rd and 4th tariff levels and the total annual domestic billed consumption in all tariff levels (1st to 4th tariff levels). According to IRAR (2009), the 3rd tariff level is defined between 15 to 25 m3/month and the 4th tariff level is defined for volumes higher than 25 m3/month. >5%
Public billed consumption (%) Ratio between annual public billed consumption and the total annual billed consumption. >5%
Economic mobility index (%) Ratio between the number of residents employed in the tertiary sector and the number of total residents. Previous theoretical models used the income variable to predict residential water demands. Cole (2004) indicates that higher levels of income can indicate higher living standards, which could imply a higher quantity of water consumption. >70%

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